1. Field of the Invention
The present invention relates to a method, user equipment and system for providing simultaneous multimedia services session by session in response to a user's request when a Push-To-Talk (PTT) over Cellular (PoC) system for supporting multimedia simultaneously provides media streams of the same media type from different sessions.
2. Description of the Related Art
With the rapid development of mobile communication and the vast extension of communication networks, various extended services and applications using mobile phones are being provided. According to various user requests, services such as positioning, multimedia and Push-To-Talk (PTT) services are being provided beyond a simple call service. Specifically, the PTT service supports various additional functions such as instant messenger and state display functions, as well as a group call and a voice call that are possible in a conventional radio system or a Trunked Radio System (TRS).
A concept of this PTT service is being actively discussed to standardize a PTT over Cellular (PoC) service using a mobile communication network. One feature of the PoC service different from the conventional mobile communication service is that users can perform communication while moving between multiple sessions according to need. The requirement that users should be able to perform communication while moving between multiple sessions is prescribed in the standard of the Open Mobile Alliance (OMA) serving as an organization for developing a standard for a mobile communication service.
On the other hand, a PoC V 2.0 system supports a PoC multimedia call service. For this, the PoC V 2.0 system defines new multimedia types of video, image and text other than voice. Further, the PoC V 2.0 system supports a multi-session function included in the conventional PoC V 1.0. The current PoC system receives multiple streams (e.g., audio, video abd image) due to performance improvement in a User Equipment (UE) and transfers the multiple streams to a user.
However, the current PoC 1.0 system is set such that a PoC server (or Participating PoC Function (PF) entity) cannot basically transmit media streams of the same media type simultaneously to one PoC UE under multiple sessions. Due to this filtering function, the low-level PoC UE does not receive user desired media streams of the multiple sessions connected thereto even when a transmission channel supports a sufficient bandwidth. Further, the current PoC system does not provide a method for performing filtering on a media type-by-media type basis or setting up a filtering target session for multimedia.
A method is being considered which can simultaneously receive all redundant media for the multiple sessions in PF by setting a PoC service value to remove filtering for the multiple sessions in the prior art. However, this method cannot apply simultaneous multi-reception services session by session. Further, there is a problem in that a simultaneous multi-reception service cannot be activated when a client participating in multiple sessions requests a new session.